1. The Field of the Invention
The present disclosure relates to drilling devices and to devices for making and breaking connections between drill rods in a drill string in particular.
2. The Relevant Technology
Drilling rigs are often used for drilling holes into various substrates. Such drill rigs often include a drill head mounted to a generally vertically oriented mast. The rig often includes mechanisms and devices that are capable of moving the drill head along at least a portion of the mast. The drill head often further includes mechanisms that receive and engage the upper end of a drill rod or pipe. The drill rod or pipe may be a single rod or pipe or may be part of a drill string that includes a cutting bit or other device on the opposing end, which may be referred to as a bit end. In the case of a drill string, the drill string may include multiple rods, each of which has a length that is shorter than the usable length of the mast.
The drill head also applies a force to the drill rod or pipe which is transmitted to the drill string. If the applied force is a rotational force, the drill head may thereby cause the drill string rotate within the bore hole. The rotation of the drill string may include the corresponding rotation of the cutting bit, which in turn may result in cutting action by the drill bit. The forces applied by the drill head may also include a generally downward force, which may be transmitted to the drill string to facilitate penetration into the substrate.
In a typical drilling operation in which the drill bit penetrates to depth that is deeper than a single rod, a head end of a drill rod is coupled to the drill head while the bit end of the rod is coupled to a head end of another drill rod. The junction between the drill rods may be referred to as a joint. The drill head is advanced from advanced from an upper position until the drill head approaches the lower end of the mast. Once the drill head has reached the lower end of the mast, a clamp or other device is used to maintain the drill string in position relative to the mast.
A breakout tool is then applied between the clamp and the joint by an operator, who is often in close proximity to the drill mast. The joint between the drill head and the first drill pipe is then disconnected (broken) via counter-rotation of the drill head. The drill head is then raised to the upper end of the mast in preparation for engagement of another drilling pipe. A new length of drilling pipe is then positioned along the centreline of the mast via the drilling rig-specific pipe handling means and the drill head is rotatingly coupled to the new drilling pipe to a manufacturer-specified torque. The drill head is then lowered such that the lower (male) end of the drill pipe is engaged into the upper (female) end of the drill string, the new drill pipe is then manually rotated into the top of the exposed drill pipe in order to accurately make the joint and then torqued to a manufacturer-specified torque via the drill head. This process is continually repeated as the drilling of the borehole continues until the desired depth is reached. Such a process may be time consuming and may place the operator in undesirable proximity to the drill mast. Further, repetitive manual movements may subject the operator to risk of injuries associated with such repetitive movements. A similar operation is often performed in removing drill rods from a drill string, which may also be time consuming and wearing on the operator.
The subject matter claimed herein is not limited to examples that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some examples described herein may be practiced.